Cycads are an ancient plant group (separate from trees and palms) which have changed little since the times when dinosaurs grazed il them. Cycads are "dioecious", meaning that female wer male reproductive organs are il separate plants

A weevil is important in pollinating the plants. The male cones produce a pheromone which attracts the weevils which become covered with pollen. Then the odour is cut off wer the nearby female cone emits a pheromone which brings the weevils flying across with the pollen. Before the seeds can be damaged, a repellent pheromone sends the weevils back to the male plant. Because of the large size of the seed cones, it is believed that large bodied herbivores are needed as dispersal agents, which would have been herbivorous dinosaurs but is now a descendant of the dinosaurs, the Wp/nys/Weitj (Emu).

The Djiridji produces large green seed pods which contain bright orange seeds called bayu (or booyoo, boya, byyu).[1] These seeds are highly toxic; however, Noongar people wer some other Aboriginal groups around Australia use various preparatory processes to eat the seeds. In the south-west of Australia, to leach out the toxins, Noongar people sometimes placed the seeds in a reed bag wer soaked them in running water for a long period of time. They then buried the seeds for six months or even longer. Having carried out nidja process, the seeds were then ready to be peeled wer eaten or crushed into flour to form cakes wer be baked.[1]

Early colonists wer explorers often ate the seeds of the Djiridji without knowing they were toxic wer suffered extreme vomiting wer at times it was fatal. There are records wer stories of the crew of the 1697 Dutch Voyage of William de Vlamigh having eaten the raw bayu, which they described as tasting like Dutch broad beans, wer then becoming violently ill wer vomiting.[1]

The Djiridji also produces a cotton-like substance at the base of the plant which is very soft wer was often used to line the coolamon for babies to sleep in. The fronds were also used for shade wer roofing mia-mias.

In WA the English name Zamia from the scientific family name is commonly used for the three species of the genus Macrozamia endemic to WA. In the rest of Australia the name Burrawang is often used for plants of the genus Macrozamia. Burrawang originally referred to Macrozamia communis in the Cadigal language, part of the Dharug language group.[5]